1. Field of the Invention
This invention relates to the field of data processing systems. More particularly, this invention relates to the control of the issue of program instructions into a processing pipeline in dependence of the availability of a write port to receive the results of the processing.
2. Description of the Prior Art
It is known to provide data processing systems with processing pipelines for performing processing operations under control of program instructions. In processing pipelines it is desirable to avoid, for example, stalls. Thus, before an instruction is issued into the pipeline, it is determined that a write port will be available at the appropriate clock cycle on any register bank which is to receive output operands from that instruction. Accordingly, when the output operands are generated by the processing pipeline, there will be no delay as a write port will be available in that processing cycle via which the output operands may be written to the register bank. This is predictive write port arbitration.